Field
The present disclosure relates to a light emitting diode (LED) package and a method for fabricating the same.
Discussion of the Background
Typically, LED packages are used for a variety of applications, such as electronic billboards for displaying letters or figures, lighting fixtures for illuminating product showcases, and the like, by providing optical output of various colors including white, red, and blue, while consuming only a few dozen Watts.
Referring to FIG. 1(a), a conventional LED package includes a package body 11 having first and second electrodes 12, 13, and an LED chip 14 mounted on the first electrode 12. The LED chip 14 is mounted on the first electrode 12 and connected to the second electrode 13 via a bonding wire W. An encapsulation member 17 is formed to cover the LED chip 14 and the bonding wire W. The encapsulation member 17 has phosphors 16 dispersed therein for color conversion.
The LED package 1 may realize white light by a combination of the LED chip 14 and the phosphors 16. Specifically, phosphors, which emit yellow-green light or yellow light using some of the blue light emitted from the LED chip as an excitation source, are dispersed above the LED chip, so that white light can be realized by combination of the blue light emitted from the LED chip 14 and the yellow-green or yellow light emitted from the phosphors 16. That is, the LED package may realize white light through combination of the blue LED chip, which is composed of semiconductor components emitting light in a wavelength range of 430˜480 nm, and the phosphors, which emit yellow light using the blue light as an excitation source.
However, in the LED package 1 shown in FIG. 1(a), non-uniform distribution of the phosphors 16 in the encapsulation member 17 can cause color deviation, due to a non-uniform optical path of the light emitted from the LED chip 14. As a result, when the LED package is applied to a secondary lens, the LED package exhibits poor optical efficiency.
A reduction in color deviation can be achieved by a process of forming a phosphor layer to a uniform thickness around the LED chip. However, this is a complicated process that should be performed under precise processing conditions. Therefore, to improve uniformity of phosphors and eliminate such problems, another conventional LED package 2 includes a package body 21, a first electrode 22, a second electrode 23, and a phosphor layer 26 formed on an upper surface of an LED chip 24, as shown in FIG. 1 (b).
With this configuration, the LED package 2 may have improved color uniformity of output light emitted from an encapsulation member 27 and through the phosphor layer 26, which has a constant thickness and is formed on the upper surface of the LED chip 24. However, since the phosphor layer 26 is disposed only on the upper surface of the LED chip 24, light emitted laterally from the LED chip 24 may result in color deviation.